Data file definition

@DATA_FILE_DEFINITION {
@DATA_FILE_NAME {DataFileName} {
@DATA_FILE_TYPE {IMPORT/EXPORT}
@INSTRUMENTATION_PACKAGE_NAME {InstPkgName}
@FILE_NAME {FileName.dat}
@FOURIER_ANALYSIS_NAME {FourierName}
@COMMENTS {CommentText}
}
}

Notes

  1. Data files provide a means of importing or exporting data to the dynamic analysis. The data contained in the data file is described by the instrumentation package, InstPkgName, associated with the data file.
    • If the data file is of type EXPORT, a subset of the computed dynamic response will be exported to the data file named FileName.dat.
    • If the data file is of type IMPORT, the data contained in file FileName.dat will be read during the simulation and will be available to perform various tasks.
  2. It is sometimes advantageous to perform a discrete Fourier transform, of the data before exporting it to the data file. If Fourier analysis FourierName is defined, a discrete Fourier transform of the data will be performed before export. If the data file is declared as IMPORT, the data file is expected to store the harmonics of the discrete Fourier transform.
  3. It is possible to attach comments to the definition of the object; these comments have no effect on its definition.

Example 1.

The data file is created by the command shown below.

@DATA_FILE_DEFINITION {
@DATA_FILE_NAME {DataF} {
@DATA_FILE_TYPE {EXPORT}
@INSTRUMENTATION_PACKAGE_NAME {InstPkgName}
@FILE_NAME {Predictions.dat}
}
}

The first three lines of the exported data file are comments. Next, come 12 integer that describe the structure of the file. The next line “---Component--- BarNumber1” lists the first component of the instrumentation package; the component label is BarNumber1. The next 12 integer provide information about the component. The next lines, “ **Gauge** Gauge1” and “ **Gauge** Gauge2” list the two gauges associated with the first component; the gauge labels are Gauge1 and Gauge2.

The above sequence is repeated for all components and all gauges of the instrumentation package to for the header of the data file.

Once the header is completed, the actual data is listed for each of the time steps. Each time step data starts with the following information “ <<<Time>>> 0.00000e+000” where 0.00000e+000 is the time. Up to six channels for each of the gauges are listed next, each gauge on one line. Note that each gauge can have up to six channels. In the present example, four lines are needed to provide the data for the four gauges. The same sequence is repeated for all subsequent time steps.

The illustrated data file was exported, i.e., the data file is of type EXPORT. This data file could be imported in a subsequent simulation.

It is possible for an external application to create a data file that satisfies the syntax requirements illustrated . Such file can then be declared of type IMPORT and read to be used by the simulation.